[Aavso-photometry] Point Spread Photometry using IRAF

[arne]

Brad Walter wrote:
> A few of us in our club are starting the journey of learning how to use
> IRAF, particularly with the goal of doing point spread photometry. We are
> using IRAF 2.12 on Ubuntu Linux 2.22 and are trying to figure out what
> packages we need to install in addition to the basic IRAF packages. In
> particular which PSF application(s) will work with this version of IRAF and
> which of these do we want to use. I see references on the internet to
> DAOHOT, DAOPHOT2 and MATPHOT. I am at the very beginning of a steep learning
> curve of both Linux and IRAF so I am not sure which questions to ask. Also
> which external packages do we need in addition to whichever PSF package to
> do preliminary processing before we can use the PSF package. I have seen
> references that indicate we need to install the DIGIPHOT and APHOT packages
> first. I'm not sure if these are internal packages or external packages that
> install with the basic IRAF installation. 
>  
> I know some AAVSO photometry discussion group members are very experienced
> IRAF users and developers.   

To the best of my knowledge, all of that material comes "preloaded" and
will be handled during the "make" process.
Once you install iraf, you need to start the program and then just
load the appropriate packages from the command line.  DAOPHOT-II is
part of iraf, and can be reached by entering

noao
digiphot
daophot

in order.  You do not need to find anything extra on the web.
Be sure to read the Massey photometry tutorial.  You might check the
download site, as I'm currently running version 2.14 of iraf.

psf fitting is an art, and I'd suggest first using the standard aperture
photometry parts of iraf to learn the system, how to display and process
images, etc.  Then get into psf-fitting.  I can give you some guidance
as you go along, and if we can find a common meeting somewhere (come to
SAS/AAVSO!), then I can give you some hands-on guidance.
Arne